1. Field of the Invention
The present invention is directed to snowplows which are operable manually and, more particularly, to a manual snowplow which is compact and portable, as well as adjustable. While the snowplow of the present invention may be used to plow widths as wide as driveways, it is basically the type which may be operated by a single individual.
2. Prior Art Statement
The removal of snow has been a concern for centuries and became more important with the development of wheel drawn vehicles and, subsequently, motorized vehicles. The prior art is replete with literally hundreds of various designs for non-motorized snow removal devices. Thus, basic devices designed for pushing snow using a single blade in lieu of shoveling snow are set forth in U.S. Pat. Nos. 637,712; 1,093,535; 1,927,196; and, 2,637,261. These patents span from the turn of the century forward and represent typical manually operated snowplows. However, these are directed to such devices which are pushed, rather than pulled, and which are directed to those having single blade members
In addition to the basic push-type snowplows developed for manual operation, in the late 1800's and early 1900's, a type of snowplow was developed which was known as the draft, which was designed to be horse drawn. These types of snowplows involved two blades instead of a single blade and many included adjustable width arrangements as well as devices for an operator to push in conjunction with a horse or team of horses pulling the device. Exemplary of these draft-type snowplows are U.S. Pat. Nos. 146,333; 163,501; 482,720; 821,660; 924,810; and, 1,331,382. While these do involve dual blades as well as adjustable width, none were designed for manual operation whereby a single operator would pull the device.
In addition to the types of snowplow technology discussed above, there has historically been push-type snowplows for manual operation which involve dual blades. Exemplary of patents representing these developments over the past century, are U.S. Pat. Nos. 194,386; 731,419; 956,896; 1,049,812; 1,307,410; and, 3,526,979. Again, these prior art references do include adjustable width arrangements for dual blades, but all involve push mechanisms for snow removal.
U.S. Pat. No 4,265,475 issued to Eugene R. Jarvis in 1981 describes a snow removal device which involves the pulling of a blade rather than the pushing of a blade by a single operator. However, this device is specifically directed to single blade operation with an adjustable pivot to change the blade angle, but does not include any advantages of the present invention device, such as adjustable width, dual blade mechanism.
Notwithstanding the formidable prior art directed to snowplow devices which span many decades, it appears that no prior art represents the improvement of the present invention involving a manual snowplow which is adjustable in width and which is specifically designed to be pulled rather than pushed. Due to the combination of running blade, ballast, optional wheels, nose guard and forward handle, it has been surprisingly discovered that the snowplow of the present invention may easily be operated by an individual of average strength without the kind of exertion necessary to move the push-type snowplows.